Leicester's mayor has dubbed the Curve theatre "the most expensive and disastrous project this city has ever seen in its history."

Peter Soulsby, who was the MP for Leicester South before being elected mayor in 2011, also revealed that the council was still incurring annual costs of £120,000 on the Curve's predecessor, the Haymarket Theatre, seven years after it closed.

The new theatre, designed by architect Rafael Viñoly, came in at £61m – more than twice the original budget – with the council's planned contribution of £4.4m eventually reaching £36.8m. "Curve is a wonderful theatre and we're very proud of it. But it came at an enormous cost and it's quite clear that when it was planned people didn't control the costs," said Soulsby.

In 2009, less than a year after the first performances in the new building, an Audit Commission judged that it did "not represent good value for money" and criticised "weak project management arrangements at the start of the project."

Fiona Allen, chief executive of the Curve, argued that the comments were not reflective of the theatre's artistic output and organisation practices.

"We're having a great deal of success," she told The Stage. "We've just had [Hollywood producer] Harvey Weinstein talking about all the reasons why he's bringing Finding Neverland to Curve – there aren't many theatres in the UK where he could bring it.

"Sales have gone up year on year, we're building audiences and our financial position continues to improve. We shouldn't dwell on the past. We really need to move forward."

Meanwhile, costs on the Haymarket, for which the council owns the lease, are down to annual maintenance costs of £100,000 and £20,000 in empty property rates.

Soulsby accused his predecessors at the city council of mismanagement: "A buyer should have been found for the Haymarket before productions moved to what is now the Curve. I'm very actively trying to find a use for the Haymarket, but it's not easy in this economic climate."